Liquid ejecting apparatus and pressure-regulating device

Abstract

A liquid ejecting apparatus includes a liquid inflow unit provided in the liquid supply path which supplies a liquid to a liquid ejecting unit and into which the liquid flows, a liquid accommodation unit having a diaphragm section, a communication path through which the liquid inflow part and the liquid accommodation part communicate, and a pressure-regulating mechanism having an on-off valve which opens and closes the communication path in response to displacement of the diaphragm portion, and a pressing mechanism which puts the on-off valve in an open state regardless of the pressure in the liquid inflow unit by pressing the diaphragm portion.

What is claimed is: 
     
       1. A liquid ejecting apparatus, comprising:
 a liquid supply path which is able to supply a liquid from a liquid supply source to a liquid ejecting unit which ejects the liquid from a nozzle; 
 a pressure-regulating mechanism provided in the liquid supply path, the pressure regulating mechanism including
 a liquid inflow part into which the liquid supplied from the liquid supply source flows, 
 a liquid accommodation part which is able to accommodate the liquid in the interior thereof, and for which the volume of the interior changes by displacing a diaphragm portion; 
 a communication path through which the liquid inflow part and the liquid accommodation part communicate, and 
 an on-off valve which enters an open state in which the liquid inflow part and the liquid accommodation part communicate from a closed state in which the liquid inflow part and the liquid accommodation part in the communication path do not communicate, when a pressure applied to a first surface which is an inner surface of the liquid accommodation part of the diaphragm portion is lower than the pressure applied to a second surface which is an outer surface of the liquid accommodation part of the diaphragm portion, and a difference between the pressure applied to the first surface and the pressure applied to the second surface is a predetermined value or more; and 
 a pressing mechanism which is provided to be able to press the diaphragm portion in a direction in which the volume of the liquid accommodation part is reduced, and which puts the on-off valve in an open state regardless of the pressure in the interior of the liquid inflow part by pressing the diaphragm portion, 
 wherein the pressing mechanism includes a pressure regulator which is able to regulate a pressure within a pressure-regulating chamber formed on the second surface side of the diaphragm portion. 
 
 
     
     
       2. The liquid ejecting apparatus according to  claim 1 ,
 wherein 
 the pressing mechanism presses the diaphragm portion by the pressure regulator regulating the pressure within the pressure-regulating chamber to be a higher pressure than atmospheric pressure. 
 
     
     
       3. The liquid ejecting apparatus according to  claim 2 ,
 wherein the pressing mechanism further includes an expansion and contraction section which is able to expand and contract and which forms the pressure-regulating chamber, and 
 the pressing mechanism presses the diaphragm portion by the pressure regulator causing the expansion and contraction section to expand. 
 
     
     
       4. The liquid ejecting apparatus according to  claim 1 ,
 wherein the pressing mechanism presses the diaphragm portion so that the pressure in the liquid accommodation part becomes higher than the pressure at which the meniscus formed at the gas-liquid interface collapses in the nozzle. 
 
     
     
       5. The liquid ejecting apparatus according to  claim 1 ,
 wherein the pressure-regulating mechanism further includes a moving member which is able to move in a state of contact with the diaphragm portion which displaces in a direction in which the volume of the liquid accommodation part is reduced, and 
 the pressing mechanism presses a region in the diaphragm portion which comes in contact with the moving member. 
 
     
     
       6. The liquid ejecting apparatus according to  claim 1 , further comprising:
 a pressurizing mechanism which is able to pressurize the liquid supplied to the pressure-regulating mechanism, 
 wherein the liquid pressurized by the pressurizing mechanism is supplied to the liquid ejecting unit in the open state of the on-off valve due to the pressing mechanism pressing the diaphragm portion. 
 
     
     
       7. The liquid ejecting apparatus according to  claim 6 ,
 wherein the pressurizing force which pressurizes the liquid is changed by the pressurizing mechanism in the open state of the on-off valve. 
 
     
     
       8. The liquid ejecting apparatus according to  claim 6 ,
 wherein the pressing state of the diaphragm portion by the pressing mechanism is released and the on-off valve is put in the closed state in a state in which the liquid is pressurized by the pressurizing mechanism. 
 
     
     
       9. The liquid ejecting apparatus according to  claim 8 ,
 wherein the liquid ejecting unit includes an actuator which is driven when ejecting the liquid from the nozzle, and 
 the actuator of the liquid ejecting unit is driven in a process which puts the on-off valve in the closed state from the open state. 
 
     
     
       10. A pressure-regulating device, comprising:
 a pressure-regulating mechanism provided in a liquid supply path which is able to supply a liquid from a liquid supply source to a liquid ejecting unit which ejects the liquid from a nozzle, the pressure-regulating mechanism including
 a liquid inflow part into which the liquid supplied from the liquid supply source flows, 
 a liquid accommodation part which is able to accommodate the liquid in the interior thereof, and for which the volume of the interior changes by displacing a diaphragm portion; 
 a communication path through which the liquid inflow part and the liquid accommodation part communicate, and 
 an on-off valve which enters an open state in which the liquid inflow part and the liquid accommodation part communicate from a closed state in which the liquid inflow part and the liquid accommodation part in the communication path do not communicate, when a pressure applied to a first surface which is an inner surface of the liquid accommodation part of the diaphragm portion is lower than the pressure applied to a second surface which is an outer surface of the liquid accommodation part of the diaphragm portion, and a difference between the pressure applied to the first surface and the pressure applied to the second surface is a predetermined value or more; and 
 a pressing mechanism which is provided to be able to press the diaphragm portion in a direction in which the volume of the liquid accommodation part is reduced, and which puts the on-off valve in an open state regardless of the pressure in the interior of the liquid inflow part by pressing the diaphragm portion, 
 wherein the pressing mechanism includes a pressure regulator which is able to regulate a pressure within a pressure-regulating chamber formed on the second surface side of the diaphragm portion.